Problem: $6cd + 8ce - 10c + 10 = 5d - 5$ Solve for $c$.
Explanation: Combine constant terms on the right. $6cd + 8ce - 10c + {10} = 5d - {5}$ $6cd + 8ce - 10c = 5d - {15}$ Notice that all the terms on the left-hand side of the equation have $c$ in them. $6{c}d + 8{c}e - 10{c} = 5d - 15$ Factor out the $c$ ${c} \cdot \left( 6d + 8e - 10 \right) = 5d - 15$ Isolate the $c$ $c \cdot \left( {6d + 8e - 10} \right) = 5d - 15$ $c = \dfrac{ 5d - 15 }{ {6d + 8e - 10} }$